Safety catch for vertically sliding doors



Sept 15, 1953 Q. 0. MOLER 2,651,817

SAFETY CATCH FOR VERTICALLY SLIDING DOORS Filed Aug. 18, 1950 2 Sheets-Sheet l INVENTOR.

Sept. 15, 1953 c. c. MOLER SAFETY CATCH FOR VERTICALLY SLIDING DOORS Filed Aug. 18, 1950 2 Sheets-Sheet 2 Patented Sept. 15, 1953 SAFETY CATCH FOR VERTICALLY SLIDING DOORS Charles C. Moler, Hartford City, Ind., assignor to Overhead Door Corporation, Hartford City, Ind.

Application August 18, 1950, Serial No. 180,269

Claims.

This invention relates to improvements in safety catch for vertically sliding doors.

The principal objects of this invention are: First, to provide an improved form of safety catch for vertically sliding doors having guide rollers travelling in a track, which catch coacts with the track with successively engageable teeth so'that the catch has a dual or emergency locking engagement should the first tooth fail or slip. Second, to provide an improved form of safety catch and guide track combination for a sliding door having a first frictional or wedging locking engagement and a second piercing engagement with a corner of the track should the first engagement slip due to spreading or bending of the track. Other objects and advantages relating to details of my invention will be apparent from a consideration of the following description and claims.

The drawings, of which there are two sheets,

safety catch installed thereon.

Fig. 2 is an enlarged'fragmentary end elevational view of the door partially broken away in vertical cross section along the plane of the line 2-4 in Fig. 3 and illustrating details of the safety catch.

Fig. 3 is a fragmentary horizontal cross sectional view through the safety catch structure taken along the plane of the line 3-3 in Fig. 2.

Fig. 4 is a fragmentary end elevational view partially broken away in vertical cross section along the plane of the line 44 in Fig. 5 showing the safety catch in actuated door holding position.

Fig. 5 is a fragmentary horizontal cross sectional view through the catch in actuated position and taken along the plane of the line 5-5 in Fig. 4: I

My safety catch consists of certain improvements in and additions to the safety catch of similar design disclosed and claimed in Patent No. 2,185,828 issued January 2, 1940, to Herbert Cady Blodgett for Safety Catch for Vertically Sliding Doors.

My catch is designed to be used in conjunction with the now familiar type of vertically sliding door in which a plurality of horizontally hinged door sections I are provided with pintle or shaft bearings 2 at vertically spaced intervals supporting the roller shafts 3. The shafts 3 carry rollers, not illustrated, which are received in and guidingly supported byv the channel shaped guide rail 4. The guide rail has a'vertically extending reach 5 secured to the walls or casing along the side of the door opening by mounting brackets 6. A horizontally extending shaft I is mounted above the door opening and provided with a pulley 8 for taking up the supporting cable 9. The shaft 1 may be power operated or as illustrated in Fig. 1 may have a spiral spring I0 wound therearound to counterbalance the weight of the door. The foregoing construction is now well known and so is not described in greater detail.

The lower door section I carries a mounting plate II at its lower end from which the angle shaped cable connecting flange [2 projects laterally of the door and inwardly of the door opening. A reenforcing plate or bracket I3 is welded to the plate II and flange I2 and projects beyond the flange I2 to form a retaining yoke for receiving the lower end of the cable 9. The cable is secured in the yoke by means of the bolt I4 and a suitable clamp I5 forming a loop in the cable.

Secured to the mounting plate I2 below the plate I3 is an angle shaped bracket I6, the inwardly projecting flange of which is apertured and coacts with the inwardly extending flange of the cable connecting flange I2 to support a short shaft IT. The laterally projecting end of the shaft I1 is rigidly connected to a generally circular roller-like catch I8 which is received between the flanges of the channel rail 4. Nonrotatably secured to the shaft I1 adjacent to the rail 4 is a generally L-shaped lever I9 having a laterally outwardly extending arm 20 on its upper end. The arm 20 carries an eye bolt 2| or other hooked fixture for embracing the supporting cable 9. A coil spring 22 wrapped around the shaft I! has one end fixed to the bracket I6, and its other end fixed to a collar 23 secured to the shaft for biasing the shaft and lever I 9 away from the door and cable 9. The engagement of the cable 9 in the eye :bolt 2| obviously prevents rotation of the shaft and lever so long as the cable is taut. However, should the cable break or the balancing or lifting mechanism on the shaft I become inoperative, the cable 9 will be immediately loosened so that the spring 22 can rotate the shaft I1 and catch member I8.

Projecting radially outwardly from the periphery of the catch I8 and at an oblique angle to the axis of the shaft I! is the tooth element 24 consisting of a hardened and pointed steel pin. The tooth 24 is mounted on the catch member I8 in such a position as to be in a downwardly directed location when the lever I9 is engaged with the cable 9 as is shown in Fig. 2.

Approximately opposite from the tooth 24, the catch I8 is provided with a cam-like projecting portion 25. Angularly advanced around the catch I8 from the tooth element 24 are a pair of teeth elements 26. The teeth 26 project radially from the catch I 8 and normal to the axis of the shaft IT. The forward or outer flange of the guide rail 5 opposing the teeth 26 is provided with a series of slots or apertures 21 which are arranged to receive the teeth 26. Both the pair of teeth 26 and the single tooth 24 are held out of engagement with the track 5 by reason of the engagement of the cable 9 with the eye 2I on the lever I9.

Upon failure of the cable 9 or the sustainagainst the forward flange of the guide rail, and

pressure of the cam projection forces the teeth 26 into the first slot 21 encountered by theiteeth 4 saidileverzis released, one flange o'f said rail having a multiplicity of vertically spaced apertures formed therein to receive said first tooth and wedge said catch member in said rail to restrain said door from iurther lowering motion.

7 .2. Safety catch mechanism for a vertically slidable door having a channel shaped guide rail a'long 'the--'side thereof and a lifting and sustainin the downward movement-of the "door. --Posi tive interlocking of the teethcdtiinithelslot 21 causes the catch member is to rotate further tightly wedging the cam projection 25 *against the inner flange of the .rail. This wedging ac- :tion should SiSOPithBIdBSCGIlt :of theadaor. .-;However shoulcl the flanges of therguide rail spread under the impact and farce. of the cam projec- LtionJS, the .door may continue .to descend. If this contingency occurs, .the 1366111. 126, which. remain in engagement with the slot 21, will-cause further rotation of .the catch memberjsl8ountil :the single oblique tooth element 24 engages and partially. penetrates the inner front corner of the guide rail. It :will belnoted that the tooth l4is longer than the teeth .25 so that its engage- ;ment with the inside-oi the guide rail serves, to .force the catelrmember 18 and .cam projection :25 further inwardly against the inner .flange of the guide rail. :Sincemost of the imomentum;.of the descending door will-have been checked by preliminary engagement .of. the teeth :26 and \camprojection 25,,theadditionalpressure of the camprojectionagainst the sinner flange of the rail will be suflicient .to bring the descending door toastop.

In order to release the catch :irom the rail, it is ;then necessary :to raise the. door manually and reestablish the tension in the .cable 9. by suitable repairs so 'thatthe cable will hold the lever 19 and catch member in operative posiition.

I have thus-described a :highly practical inexpensiveformof safety catch having the desired double catch safety feature so that others may understand the construction and operation thereof. I have not attempted to show other possible variations ;or modifications of mycatch, but I do not :intend :to limit'mysinventionto the particular 'form of catch illustrated and intend to limit my .invention only as set forth in the following claims.

"Having thus described my invention; what I claim as new and desire to secure by Letters Patent is 1. A safety door catch for a verticallyfislidable 'door having a vertically extending guide rail of channel shaped cross section. positionedyalong the edge of the door and a cable secured to the bottom of the door adjacent to said guide rail for-lifting and sustaining the door, said catch comprising a shaft rotatablysupportedmear the bottom of said door and projecting laterally in- Lto-the channel of said guide trail, a-catch member secured to said shaft within said channel, spring means biasing said shaft and-catch member-rotatively, .a lever secured to said shaft and having an interlocking engagement *With :said cablew-remote from said shaft to;resist-said spring means :so long as said cable ,:is:taut,:*a flrstitooth proj ecting'from said catch member at a radial angle with respect ito said shaft, andxa secondary tooth projecting .radiallyrand obliquely with respect to saidsshaft and angularly displaced on said catch member behind said first tooth, said second tooth having a .hardenedpoint adapted to engage thetcorner of :said'rail when ingcable-securedto the bottom thereof, said mechanism-comprising a rotatable catch member mounted on saiddoor and projecting into the channelof said rail, said catch member having a projecting portion thereon rotatable into wedging engagementv with a.flange of said .raiL-spring means biasing .said i catch :member into ;wedglng position, .a lever secured .to said catch member and engageable withsaid cable to renderzsaid spring means inoperative when said cable is taut, aifirst rail engaging tooth on :said catch member projecting radially from the opposite side thereof from said projectionandasecondary tooth projecting radially from said catch membenand at an oblique angle to :the axis-of said catchlmember-toengage the-interior corner of said rail and positioned angularlyr-behind said first :tooth, said other flange having a plurality of vertically spaced recesses formed therein for, receiving and engaging saidflrst tooth.

.3. Safety-catch mechanism for, a iverticallyslidable door having a channel .-shaped;v-guide :rail along the side thereof and alifting and'sustain- .ing cable secured to the bottom thereof, said mechanism-comprising, a rotatable catch member mounted on said door and projecting into the channel of said rail, said catch member having a projecting portion thereonrotatableinto wedging engagement with a'flange of said rail, spring means biasing said catch member into wedging position; a lever secured to said, catch member and engageable with said cable to render said spring means inoperative when said rcable is taut, and a rail engaging tooth on said catch member projecting radially'fromthe opposite side thereof from said projection and at an-oblique angle to the: axis of...said catch member .to en age the interior corner of :said .rail.

4. A safety catch for vertically slidable doors comprising, a rotatable catch member projecting from the-side of said sdoor, spring -means biasing said catch memberto'locking position,;a:channel shaped rail; disposed: along the side. of said door and within-whichsaid catchmemher-is translatable, a wedging projection on said catch mem-- ber engageable 'with one flangeof said rail, and a tooth projecting from said catch member oppositely-from-said projection, the other flange of saidrail havingraplurality of .verticallyzspaced holeszformedatherein. forreceiving said tooth. v

5. A safety catch member for a vertically-slidlableudoor comprising a rotatable element carried 133 75316. vdoor and spring biased to locking position, a wedgingprojectiononrsaid .catch member and a pointedtooth projecting .from said member radially, opposite said. projection and inclined obliquelyvto the axis of saidcatch member to .engage theinterior .corner of .a guide .railior said door.

CHARLES C.MOLER.

References Gited inthe file of this patent UNITED STATES :PA'I'ENTS 

